PUFF

[kayakdiver] is developing a SIP and PUFF controlled kayak, but in order to start you first need a SIP and PUFF switch. These devices allow the user to lightly sip or puff into a tube to control switches or sensors, and are sometimes mounted in joysticks for control of a computer, or wheelchair, etc, but finding the cost prohibitive the next best thing was to whip up their own.

The design is clean and direct featuring off the shelf tubing and fittings, 2 pressure/vacuum switches, and an Arduino. Each one of the switches can detect pressure or vacuum, so one switch set to each is fed though a Y and up to the mouthpiece, since everything is sealed this has the advantage of only needing pressure and not airflow making it more comfortable for the user over long periods, and keeps down on humidity in the tubes.